diff --git a/pkgs/build-support/writers/default.nix b/pkgs/build-support/writers/default.nix
index 3016a45b8a0f..faac553dee3f 100644
--- a/pkgs/build-support/writers/default.nix
+++ b/pkgs/build-support/writers/default.nix
@@ -340,6 +340,7 @@ let
     };
 
     fsi = writeBash "fsi" ''
+      export HOME=$NIX_BUILD_TOP/.home
       export DOTNET_SKIP_FIRST_TIME_EXPERIENCE=1
       export DOTNET_CLI_TELEMETRY_OPTOUT=1
       export DOTNET_NOLOGO=1